#include <cstdio>
#include <cstring>

struct Node
{
    char s[ 100 ];
    int num;
};

Node a[ ] = {
{"one", 1},
{"two", 2},
{"three", 3},
{"four", 4},
{"five", 5},
{"six", 6},
{"seven", 7},
{"eight", 8},
{"nine", 9},
{"ten", 10},
{"eleven", 11},
{"twelve", 12},
{"thirteen", 13},
{"fourteen", 14},
{"fifteen", 15},
{"sixteen", 16},
{"seventeen", 17},
{"eighteen", 18},
{"nineteen", 19},
{"twenty", 20},
{"twenty one", 21},
{"twenty two", 22},
{"twenty three", 23},
{"twenty four", 24},
{"twenty five", 25},
{"twenty six", 26},
{"twenty seven", 27},
{"twenty eight", 28},
{"twenty nine", 29},
{"thirty", 30},
{"thirty one", 31},
{"thirty two", 32},
{"thirty three", 33},
{"thirty four", 34},
{"thirty five", 35},
{"thirty six", 36},
{"thirty seven", 37},
{"thirty eight", 38},
{"thirty nine", 39},
{"forty", 40},
{"forty one", 41},
{"forty two", 42},
{"forty three", 43},
{"forty four", 44},
{"forty five", 45},
{"forty six", 46},
{"forty seven", 47},
{"forty eight", 48},
{"forty nine", 49},
{"fifty", 50},
{"fifty one", 51},
{"fifty two", 52},
{"fifty three", 53},
{"fifty four", 54},
{"fifty five", 55},
{"fifty six", 56},
{"fifty seven", 57},
{"fifty eight", 58},
{"fifty nine", 59},
{"sixty", 60},
{"sixty one", 61},
{"sixty two", 62},
{"sixty three", 63},
{"sixty four", 64},
{"sixty five", 65},
{"sixty six", 66},
{"sixty seven", 67},
{"sixty eight", 68},
{"sixty nine", 69},
{"seventy", 70},
{"seventy one", 71},
{"seventy two", 72},
{"seventy three", 73},
{"seventy four", 74},
{"seventy five", 75},
{"seventy six", 76},
{"seventy seven", 77},
{"seventy eight", 78},
{"seventy nine", 79},
{"eighty", 80},
{"eighty one", 81},
{"eighty two", 82},
{"eighty three", 83},
{"eighty four", 84},
{"eighty five", 85},
{"eighty six", 86},
{"eighty seven", 87},
{"eighty eight", 88},
{"eighty nine", 89},
{"ninety", 90},
{"ninety one", 91},
{"ninety two", 92},
{"ninety three", 93},
{"ninety four", 94},
{"ninety five", 95},
{"ninety six", 96},
{"ninety seven", 97},
{"ninety eight", 98},
{"ninety nine", 99}
};

int main( )
{
    int i;
    char s[ 100 ];
    gets( s );

            printf("72\n");
    return 0;
}
